hi folks first post here, I have been looking into the exact same thing, for me i'm going on wall. I have auditioned the B&W XT2's and i thought they sounded great. BUT, the XT4's should really be the mains, and they are floor standers, so I have been going back and forth with this. I also auditioned the Anthony Gallo Refrence3 AV, and although a bit more pricey then the B&W, I loved the sound of those as well. I think the B&W had a little better low end, but I have a sub already and I just feel the gallos, can handle more power, and will also grow with my system better. I tried to find a dealer with the Def Techs Mythos8's but no luck. I would have really liked to hear them, I heard good things about them. Finally I think I am going with the Gallos, also because the reviews on them are all VERY positive! Good luck!

Good choice. Having reviewed them personally I can say without a doubt, that the Gallo's are a fine speaker and some of the best on-walls out there today. I wish you could've heard the Def Tech's too, but trust me, you won't be sorry with the Gallo on-walls. Enjoy.